Continuous elevators having automatic charging and discharging

ABSTRACT

The present invention relates to continuous elevating and lowering devices disposed in back-to-back relation utilizing balancers carrying containers and mobile ejectors for removing the containers from the elevator. The mobile ejectors of the present invention include an ejection arm subject to pivotal movement controlled by a cam which cam provides successive movements for removal of a stop which prevents swinging of the container; begins disengagement of the container from the elevator by a push arm and ends the pushing of the container into disengaged position by a second push arm. The mobile ejector removes the containers from the elevator without balancing them and the containers remain in a substantially vertical position during removal.

United States Patent [72] Inventor Claude Carlier Montreuil, France [21] Appl. No. 82,417 [22] Filed Oct. 20, 1970 [45] Patented Jan. 11, 1972 [73] Assignee Saunier Duval Montreuil/S-Bois (Seine), France [32] Priority Oct. 24, 1969 [33] France [31] 6936475 [54] CONTINUOUS ELEVATORS HAVING AUTOMATIC CHARGING AND DISCHARGING 5 Claims, 6 Drawing Figs.

[52] U.S. Cl 193/20 [51 Int. Cl 865g 47/00 [50] Field of Search 198/140, 141,145, 148, 155,158, 177, 129, 20;2l4/l6.l4

[56] References Cited UNITED STATES PATENTS 748,576 H1904 Bivert 198/145 Primary Examiner-Richard E. Aegcrter Anorney-Cameron, Kerkam & Sutton ABSTRACT: The present invention relates to continuous elevating and lowering devices disposed in back-to-back relation utilizing balancers carrying containers and mobile ejectors for removing the containers from the elevator. The mobile ejectors of the present invention include an ejection arm subject to pivotal movement controlled by a cam which cam provides successive movements for removal of a stop which prevents swinging of the container; begins disengagement of the container from the elevator by a push arm and ends the pushing of the container into disengaged position by a second push arm. The mobile ejector removes the containers from the elevator without balancing them and the containers remain in a substantially vertical position during removal.

PATENTEUJANI 1 ma 34633'726 snmiora CONTINUOUS ELEVATORS HAVING AUTOMATIC CHARGING AND DISCHARGING BACKGROUND OF THE INVENTION The present invention relates to continuous elevating and lowering devices of the back-to-back type using balances for containers.

In the field of handling and more particularly of handling of loads between different levels of a factory, elevators are now used essentially made up of two endless chains driven in continuous movement which support at regular intervals coupling balances engaging containers or other receivers for the charge to be transferred. It is well known that these balances are suspended on the chain at regular intervals and in such a way that the coupling arms of the balances occupy, when empty, a horizontal position in the direction of the loading station. When passing one of the loading stations, the arms couple to the ears of a container which is suitably placed for this purpose and the weight of which when empty is sufficient to move the arms into a substantially vertical position. The load is thus transferred from one level to another within a vertical shaft which may include guide rails to prevent swinging of the load. Each level may be provided with a platform providing access to the elevator charging and discharging positions.

Automatic discharge of this type of elevator requires the use of discharge mechanism to disengage the containers from the balances at a selected level and usually include safety apparatus preventing removal of the container if access is not available to the discharge ramp and to the discharge platform.

A system of discharge is known and is called at fixed level which consists essentially of providing at each level a system of pivoting arms mounted on the discharge platform which pivoting arms are located in the trajectory of the containers to engage the balance and move the balance laterally in the direction of the discharge area. These discharge arms may carry a roller engaging a guide opening in the balance. Further, the movement of rotation of the arm from the at rest position forward the balance engaging position may control the operation of a safety gate in the direction of movement of the containers. This discharging system is usually used in large installations having numerous levels when it is necessary to avoid any overloading of the chains. In most installations, it is preferred to employ a discharge system called mobile ejector" in which adjacent each balance, the chain supports an ejector which moves with the chain and control apparatus at each discharge station selects the desired container. Discharge apparatus actuated by a cam then removes the container, indexing means on the container actuating the control apparatus. This discharge system has the advantage of avoiding the use of charging or discharging mechanism in the path of movement of the containers carried by the conveyor and provides an installation in which the charging and discharging of the balances cannot be blocked. However, this system has certain inconveniences which are usually found in the final stages of discharge, that is, at the moment when the mobile ejector controlled by the cam rotates and bears against the side of the container to push the container in the direction of the discharge station. This maneuver institutes a tipping of the container up to the time of disengagement of the balance. This tipping is principally due to the fact that the point of application of the mobile ejector on the container is at the lower portion of the container.

SUMMARY OF THE INVENTION Apparatus in accordance with the present invention avoids this inconvenience and provides a discharge system with mobile ejector which considerably improves operation and safety of the system.

In accordance with the present invention, a mobile ejector is associated with each balance and has a number of arms, mounted on a shaft which is mounted in corresponding links at the same position of a pair of chains, the arms having on at least one of their extremities a roller engaging a fixed cam to III rotate the arms in predetermined order to provide the following successive functions:

Removal of an antiswing stop for the container;

Beginning of movement of the container toward the discharge station by pushing the container with one of the arms engaging the lower part of the container; and

End of movement of the container by pushing the container with another of the arms engaging the upper part of the container.

BRIEF DESCRIPTION OF THE DRAWINGS A preferred embodiment of the present invention is shown in the accompanying drawings and is described hereinafter with reference to the drawings for a better understanding of the invention. In the drawings, in which like reference characters indicate like parts:

FIG. 1 is a schematic view in lateral elevation of a preferred embodiment of the elevating and lowering device of the present invention;

FIG. 2 is a front view in vertical elevation of the mobile ejector and a container in at rest position;

FIG. 3 is a side view of the structure of FIG. 2; and

FIGS. 4, 5 and 6 are schematic views in lateral elevation of the different successive phases of movement of the container to the discharge position.

DESCRIPTION OF THE PREFERRED EMBODIMENT The elevator shown schematically in FIG. 1 has a pair of endless chains 1 carrying at regular intervals pairs of balances 2 and ejectors 3 for automatic charging, transporting and automatic discharging of containers 4, the chains being riven by a motor, which is not shown, to serve a plurality of levels or stages of a factory. The pair of chains 1 is carried by a pair of upper wheels, not shown, on an axis 6 which wheels driven the chains and the chains are returned on a pair of lower wheels, not shown.

As thus constituted, the pair of chains 1 circle between the levels to be served in the direction indicated by the arrow as seen in FIG. 1. Upward movement is carried out at the left and descending movement is carried out at the right as seen in FIG. 1. In known manner, vertical shafts with guide rails may be used around the vertical reaches of the chain.

Balances 2 are mounted on a shaft having rollers at each extremity thereof and passes through links at the same level of the pair of chains 1. Each shaft has on each side thereof an arm 7 which carries counter weight 8 and arms 7 are counter balances so that in their equilibrium position arms 7 are substantially horizontal.

FIGS. 2 and 3 show a container 4 generally of rectangular parallelopie pedal form to receive the charges to be carried by the elevator. Container 4 has recessed cars 10 under which arms 7 are engaged to lift the container and to support it from the charging station to the discharging station. It is well known that these containers may carry indexing devices, for example, contacts 11 and 12 which control discharge of an appropriate container, when the container has passed an indexing device. The different contacts 11 and 12 are in preregulated arrangement.

Ejectors 3 are mounted similarly to the balances 2 on a shaft 9" passing through the links at the same level of the pair of chains 1 and shaft 9 has at its extremities rollers 13 mounted in the same guide rails, not shown, as the rollers, not shown, for balances 2. Each ejector 3 is associated with a balance 2 and precedes its balance in the direction of movement of the conveyor. The distance between shaft 9 and the axis of balance 2 is such that, in the vertical reaches of the chain, the bottom of container 4 suspended by its ears 10 and by arms 7 of balance 2 comes within several centimeters of shaft 9 and close to the several discharge arms of ejector 3.

Ejector 3, shown in FIGS. 2 and 3, forms an assembly connected to chains 1. It is essentially made up of the following elements which pivot on shaft 9. The first element is a lever 14 having a stop 14a at one extremity restraining container 4 to avoid swinging thereof. The other extremity of lever 14 carries a roller 14b. A first discharge mechanism 15 has two arms 15a and 15b carrying rollers 16a and 16b at their extremities. Roller 16a engages the lower part of container 4. A second discharge mechanism 17 is made up of two arms 17a and 17b having rollers 18a and 18b at their extremities. It will be noted that the ejection arm 17a is disposed opposite arm 15a. Arm 17a much longer than arm 15a and roller 17a engages the upper portion of container 4.

The ejector thus has three elements which pivot independently on shaft 9. Each of these elements is maintained in the position shown in FIG. 3 by appropriate springs. Lever 14 is maintained by spring 18. The first discharge mechanism 15 is maintained by spring 19 hooked to an extension 150 of arm 15a. Springs 18 and 19 are fixed to pins connected to chain 1. In the same way the second discharge mechanism 17 is maintained in position by spring 20 fixed to the other chain 1 and to an extension 170 of ejection arm 17a.

The assembly thus formed is maintained by the springs in the position seen in FIGS. 2 and 3, which position is shown schematically in FIG. 1 for the containers located in the descending reach of the chains between the discharge stations.

A cam 21 is shown in FIGS. 2 and 3. A cam 21 is located at the level of each discharge station. It is seen in FIG. 2 that cam 21 is of predetermined length such that rollers 14b, 16b and 18b, which lie in substantially the same vertical plane, come in contact with it during the descending movement of the chains. FIG. 3 shows the profile of cam 21 which includes a predetermined number of inclined flats A, B, C and D whose function will be explained hereinafter.

Cam 21 may be rotated about its vertical axis. In FIGS. 2 and 3 the operating position of cam 21 is shown in solid line and cam 21 is shown in inoperative position in broken line.

Safety stops 22 and 23 may be used for disengagement of arms 7 from container 4 with a very restricted limit and may also be used to cause discharge of the container upon breaking of a spring.

Referring now to the several figures, the elevator operates as follows. In FIG. 1 the different phases of charging, transporting and discharge of the container from the elevator are represented at a a to e, respectively.

The charging position at a includes an access door, not shown, by which container 4 is introduced manually or automatically to a position on charging platform 25 in such a position that the arms 7 of balance 2, in horizontal position, move into engagement with ears l0 and transport the container upwardly.

At b the arms of the balance have moved from the charging station and the consecutive movements of the container from a to b may be improved by suitable means, for example, by a guide plate 24 which may swing from the vertical in response to the weight of container 4. As described above, immediately above balance 2 is mobile ejector 3.

Phases c and d show the movement of the containers to the vertical run of the chains along which the discharge stations are located. When the containers are suspended in the descending vertical path (phase d) they are suspended in the vertical axis of balance 2 and mobile ejector 3 is located immediately beneath the container in the position shown in FIG. 3. At this time stop 14a is applied against the side of the container and limits swinging of the container. The discharge position e has a staging including a ramp for the containers .received on discharge platform 26. This discharge position may include any desired means for removal of the containers such as a rotary table, rollers, or a motorized belt. Each discharge station may include an indexing device, not shown, located above the discharge platform which selects, using the indexing contacts 11 and 12 on the containers, the containers to be discharged at that position.

If the code indexed on the container does not correspond to that for a given discharge position, the balance passes this position without the discharge of the container.

On the other hand, if the code indexed on the container corresponds to that of the discharge station, cam 21, mounted at that discharge station is moved to the position shown in FIGS. 2 and 3. Cam 21 then causes discharge of the container as il lustrated in FIGS. 4, 5 and 6 which show the several steps of the discharge movement of the container at discharge position e.

During descending movement of the chains 1, rollers 14b, 16b and 18b engage cam 21 and cause the rotation of members 14, 15 and 17 with which they are associated.

As seen in FIG. 4, roller 14b is the first to engage flat A of cam 21 and causes rotation of lever 14 and movement of stop 14a away from the container. Container 4 remains in vertical position. Roller 16b then engages cam 21 and pivots first e jection arm 15a and roller 16a of this arm presses against the lower part of container 4 to move container 4 toward the discharge position.

FIG. 5 illustrates the second phase of discharge during which stop 14a is completely removed and discharge arm 15a remains applied against the container. Roller 18b of the second discharge mechanism 17 now engages the flats A and B of cam 21 causing ejection arm 17a to pivot with container 4 already inclined to the vertical under the action of ejection arm 15a.

FIG. 6 shows the last discharge phase. Rollers 14b and 16b return to their original position rolling on face B of cam 21. Roller 18b is then on flat C and consequently ejection arm through roller 18a bears on the upper part of the container 4 causing a double action, the first part of this action continues the movement of container 4 started by ejection arm 15a now in its final position while the second part of the action straightens the container since arm 17a bears on the upper part of the container.

Because of this double action exerted at the bottom and at the top of the container by the ejection arms, the container is now in a substantially vertical position no matter what the position of the center of gravity of the container. Further, the components of movement of discharge are such that the container arrives on platform 26 at practically zero velocity which is an important advantage in that the discharge is carried out without shock wither to the materials of the device or to fragile objects carried by the containers.

When rollers 14b and 16b move toward the bottom of cam 2], arms 14 and 15 are rotated by springs 18 and 19 and return to their first positions. Arm 14 is at this moment several centimeters below the discharge platform 26 and is in a substantially vertical plane because of arm 17a which continues to act on the upper part of container 4 until container 4 rests on platform 26.

The descending movement of the chains continues and roller 18b disengages from the cam after passing over flat D and arm 17a is returned to its original position by spring 20. At this time arm 7 of balance 2 disengages from beneath ears 10 of container 4 and the discharge cycle is completed.

The present invention has been described for a preferred embodiment. It is obvious that the movement of the containers from the discharge station can be carried out from either side of the station in any known manner. Further, the discharge arms and the cam can be disposed in symmetrical positions other than those which have been described.

What is claimed is:

1. A continuous elevator comprising a pair of spaced endless chains, vertical ascending and descending runs for said chains, balances on said chains, a pair of spaced arms on each of said balances for automatically engaging a container at a loading station on the descending run of said chains for movement by said chains, a mobile ejector carried by said chains adjacent each of said balances, said ejector including a shaft carried by said chains, a plurality of arms rotatably mounted on said shaft for independent rotation, a cam at a container discharge station, means on each of said arms engaging said cam for rotating said arms, at least two of said arms being of different lengths, said cam rotating the shorter of said two arms into engaging position with the lower portion of said container moving the lower portion of said container laterally toward the discharge station, said cam then rotating the longer of said two arms into engagement with the upper portion of said container moving the upper portion of said container laterally toward the discharge station whereby said container reaches the discharge station at minimum velocity and remains in substantially vertical position during its lateral movement.

2. An elevator as described in claim I, said cam terminating rotation of the shorter of said two arms while continuing the rotation of the longer of said two arms whereby said container is rotated about the shorter of said two arms into substantially vertical position.

3. An elevator as described in claim 1 including a stop mounted on one of said plurality of anns engaging said container preventing swinging thereof on said arms, said cam first rotating said one of said arms and disengaging said stop from said container.

4. An elevator as described in claim 1, said means on each of said arms engaging said cam lying substantially in the same vertical plane and said cam having a plurality of successive flat angularly disposed cam surfaces engaged by said means.

5. An elevator as described in claim 1 including springs holding said arms in an equilibrium position prior to engagement by said cam, said stop holding said container in substantially vertical position on the descending run of said chains.

4 i t i l 

1. A continuous elevator comprising a pair of spaced endless chains, vertical ascending and descending runs for said chains, balances on said chains, a pair of spaced arms on each of said balances for automatically engaging a container at a loading station on the descending run of said chains for movement by said chains, a mobile ejector carried by said chains adjacent each of said balances, said ejector including a shaft carried by said chains, a plurality of arms rotatably mounted on said shaft for independent rotation, a cam at a container discharge station, means on each of said arms engaging said cam for rotating said arms, at least two of said arms being of different lengths, said cam rotating the shorter of said two arms into engaging position with the lower portion of said container moving the lower portion of said container laterally toward the discharge station, said cam then rotating the longer of said two arms into engagement with the upper portion of said container moving the upper portion of said container laterally toward the discharge station whereby said container reaches the discharge station at minimum velocity and remains in substantially vertical position during its lateral movement.
 2. An elevator as described in claim 1, said cam terminating rotation of the shorter of said two arms while continuing the rotation of the longer of said two arms whereby said container is rotated about the shorter of said two arms into substantially vertical position.
 3. An elevator as described in claim 1 including a stop mounted on one of said plurality of arms engaging said container preventing swinging thereof on said arms, said cam first rotating said one of said arms and disengaging said stop from said container.
 4. An elevator as described in claim 1, said means on each of said arms engaging said cam lying substantially in the same vertical plane and said cam having a plurality of successive flat angularly disposed cam surfaces engaged by said means.
 5. An elevator as described in claim 1 including springs holding said arms in an equilibrium position prior to engagement by said cam, said stop holding said container in substantially vertical position on the descending run of said chains. 